of detroit



UNITED STATES PATENT OFFICE.

LOUIS JAENICHEN, 0F DETROIT, MICHIGAN, ASSIGNOR TO THE STANDARD COMPUTING SCALE COMPANY` OF DETROIT, MICHIGAN, A CORPORATION OF MICHIGAN.

SCALE.

, Specification of Letters Patent.

Patented Aug. ,22, 1916.

Detroit. in the county of Wayne and State' of Michigan, have invented a new and useful Scale, of which the following is a speciiication.

This invention relates to spring-scales provided with fan-shaped dials properly graduated and printed to represent the weight and value of the article on the load receiving pan or platform, in which scales an arm or pointer swings across the dial under the force exerted on a lever by the load, which force is resisted by a spring; and the object of this invention is to provide a scale ot' this type with means whereby the pointer will always be caused to indicate the correct amounts at all temperatures.

This invention consists, in combination with a base and a main load receiving lever mounted thereon, a spring to resist the movement of the lever, a pivoted arm to indicate movements of the lever, a thin metal tape connecting to said arm, and a thermostatic device, preferably of horseshoe form, connected to said lever and to said ytape in such a manner that changes of temperature will not only vary the effective length of the lever arm to which it is connected, but will also vary the initial relation of the pointer and lever so that the pointer will approximate zero so long as there is no load on the pan or platform.

In the accompanying drawing, Figure 1 is a view in elevation of the upper part of a scale with the back of the housing removed and in longitudinal vertical section of the base. Fig. 2 is an elevation on a larger scale of a thermostatio device connected to the main lever and to the tape that controls the indicator. Fig. 3 is an elevation of a modified form of thermostatic device. Fig. 4 is an elevation of a modified ,form of connection between the thermostat and the indicator.

Similar reference characters refer to like parts throughout the several views.

In the present construction, which is similar in many respects to the construction shown `in my former application No. 24627, tiled April 29, 1915. the base 1` pedestal L having arms 3 to support the bearings 4 of the, knife edges 5, the lever (3 having knife edges 7 on which rest the bearings S` of the spider 9 for the plate, platform or pan 1U, the check-rod 12. the check-link l-.1 the bracketli to which the link 1B connects. tho tare-beam 15 and its poise lo. the dash-pot 1T. the bracket 1S, the spring 19. and the housingr 2() may be of any desired vconstruction'and form no part of the present invention.

Secured to the housing 20 is a pair of brackets 22 which carry the bearings for the. pivot 23 of the indicating arm or pointer 24, preferably provided with an indicating thread or wire :25. A counterlmlancing arm 26 extends oppositely to the pointer and a, hub 2T may also he connected to this pointer. A thin metal tape 28 may be secured to this hub by means of the screw 29, a counter weight 3o on one end of the tape serving to swing the pointer when permitted to do so by the rising of the. adjacent end of the lever' G. Instead of directly connecting this metal tape 25 to the main lever, this invention interposcs a thermostat between them, which is preferably set, at such an angle that it will have peculiar values. rl`histhermostat 3:2 ils preferably horse-shoe shaped with the two arms extending at such au angle that when the arms move toward each other` the etiective length of the lever arm is decreased and at the same time the pointer 25 is swung back toward the zero mark. By using a metal strip of greater coefficient ol' expansion on the outside and a strip 3i ol lesser coefiicient on the inside, the eii'cctive distance from the pivot 5to the end of the thermostat will decrease with increasingr temperature. That is, as the spring 19. becomes weaker becauseof the increase in temperature and therefore expands greater distances for the same increase in load. this thermostat will decrease the lei er arm that actuatcs the tape 2S which will therefore be moved less distances for equal angular movements of the lever (3. At the saine time the initial eX- pansion of the spring because of increasing temperature will permit the adjacent arm ot the lever to rise, but the same increase in temperature will cause the end 350i' the thermostat to swing down, thus counterbalancing its upward .movement because of the* expansionv oit the spring.

While this device has been shown connected to a simple leverit will be apparent that it may be used on levers ot any type or system. lt will also be apparent that the construction and location of the thermostatie device may be changed. The construction shown in Fig. 3 consists of two thermostats, the upper one consisting of the slightly curved cross-bars 38 and 39 preferably of steel, and the cross-bar t0 ot brass between them, with their adjacent ends rigidly secured together. This thermostat Will take care of the initial expansion of the spring and cause the indicator to remain at zero when the scale is unloaded. The upper cross-bar connects to the tape 37, While the lower cross-bar 39 connects to the curved bar tl ot' the second thermostat, which is also built up in the same manner as the first, the bars 41 and 42 preferably being of steel and the bar t3 of brass. As the spring becomes weaker with increasing.temperature, the effective length of the arm of the lever to` which the band 37 is connected also decreases, so that the ettect on the Weight indicator of equal increments of load remains the same.v

lnstead of a flexible connector 28 passing around the hub 27 of the indicator, a pinion t5 may be secured to the pivot Q3, and a rack bar +16 connected' to the thermostat 3:2 and held in engagement with the pinion. In this case as in all others, the parts must be proportioned so that the reduction of moven'xent of the indicator will be in proper relation to the increased rate of expansion otthc spring.

l claim z-- 1. ln a scale, thecombination ot a baseA and a pedestal tl'iereon, a scale lever mounted on the pedestal, a load receiver connected to one arm ot' the lever, a load-resisting spring connected to the other arm ot' the le i ver, a pivoted weight indicator mounted adjacent the spring, ay hub connected to the indicator. a flexible band secured intermediate its ends to said hub, a counterweightsecured to one end ot the band, and a thermostat connecting the opposite end of the band to the lever.

2. ln a. scale, the combination of a base and a pedestal thereon, a scale lever pivoted intermediate its ends on the pedestal, a load receiver connected to one arm ot' the lever, a load-i'esisting spring connected to the other arm of the level', a pivoted Weight indicator mounted adjacent the arm of the lever to which the spring connects, a cirmesma cular hub connected to the pointer. a flexible hand secured intermediate its endsI to said hub, a counterweight secured to one end of the band, and a thermostat connected to said band and lo the adjacent end of the lever, said thermostat being formed of two metal strips bent to horse-shoe form.

3. ln a scale, the combination ot a scale lever and a support therefor, a load receiver and a load-resistingspring connected to the lever, a Weight indicator adjacent to one arm of the lever, a. flexible band to control the operation of the weight indicator, and a horse-shoe shaped thermostat connecting the band and lever and having its arms at an angle to the lines. of the lever and ot' the band.

4. In a scale, the combination of a scale lever and a support therefor, a load receiver and a load-resisting spring connected to the lever, a weight indicator adjacent one arm of the lever, a horseshoe shaped thermostat mounted on said arm of the lever, and a connector between the thermostat and the weight indicator, said thermostat being so mounted that the end of the connector will be moved diagonally to the line of the lever with changes in tempera-ture.

5. In a scale, the combination of a scale lever and a support therefor, a weight indicator, a horse-shoe shaped thermostat having one arm so connected to said lever that the other arm will move diagonally to the line of the lever with changes ot tcmperature, and means connecting said other arm to the weight indicator.

6. ln a scale, the combination ot' a scale lever, a support therefor, a load receiver and a load-resisting spring connected to thcl lever, a pivoted Weight indicator, a flexible band to control the operation of the weight indicator, and a thermostat so connected to the flexible band as to reduce the distance between the pivoted indicator and the lever in proportion to the relative expansion ot the spring due to a rise in temperature.

7. In a scale, the combination ot' a scale lever and a support therefor, a load receiver and a load-resisting spring connected lo the lever, a Weight indicator, a thermostatic device mounted on said lever, and a connector between the thermostatic device and the Weight indicator, said thermostatic device being so mounted that the end ot' the connector will be moved diagonally to the line of the lever with changes in temperature.

8. lln a scale, the combination ot a scale lever and a support therefor, a weight indicator, an operating member connected to said indicator, and a thermostat connecting said operating member to the scale lever,

9. ln a scale, the combination ot' a sale lever and a support therefor, a weight indicator, a thermostat rigidly connected to one end of said lever, indicator operating means arm of said lever, and Weight indicator acconnecting directly to said thermostat, and tuating means connecting directly to the means for resisting the action of the load 10 thermostat. upon said lever.

5 10. In a scale, ithe combination of a scale In testimony whereof I sign this specifilever and a support therefor, a Weight indication.

cator, a thermostat rigidly connected to one LOUIS JAENICHEN. 

